1. Field of the Invention
The present invention relates to spine fixation components, constructs and assemblies.
2. Background Information
Spinal orthopedic assemblies and constructs such as spine plates, spinal bone screw assemblies for spinal rods and other devices (spinal components) have made a profound contribution to the correction of spinal deformities, accidents and other problems in the thoracic, lumbar and sacral spine. These and other spinal devices are typically fixed to vertebrae using vertebral bone screws. Vertebral bone screws are specially designed and manufactured bone screws that are placed into the bone of a vertebra. One typical placement of a bone screw for the fixation of a spinal component is through a pedicle of the vertebral body. Vertebral bone screws placed in this manner offer superior strength and pull-out resistance as compared to other forms of fixation in spine surgery. The ability to achieve pedicle fixation has allowed surgeons to obtain more secure fixation of the involved vertebral segments, which permits more powerful correction of spine problems and reported better clinical outcomes. Vertebral bone screws for pedicle fixation may be known as pedicle screws.
In addition to other uses, pedicle screws provide a solid foundation for the attachment of spinal rods. Spinal rods are used for the fixation of a plurality of vertebrae for various situations. A spinal rod is held relative to a pedicle screw by a spinal rod connector assembly attached to the pedicle screw. Various types of spinal rod connector assemblies are known such as those that allow for inter-operative adjustments in the coronal, transverse and sagittal planes. Certain spinal rod connector assemblies allow for various degrees of freedom for attachment to a pedicle screw from any direction, angle, and height. In all cases, however, the spinal rod connector assemblies hold a spinal rod and are fixed relative to the pedicle screw.
In this manner, spinal rods can be rigidly locked into a variety of positions along with other types of implant components. This allows a surgeon to tailor-make each construct for the individual case. In addition, some spinal rod connector assemblies are designed to provide for no in-situ threading. This decreases operative time by allowing the spinal rod connector assembly to be pre-assembled while the surgeon places the pedicle screws.
Even with the flexibility offered by the various prior art spinal rod connector assemblies, there is room for improvement.